Lighting unit



Dec. 2, 1941. F. c. wlNKLER x-:rAL

` LIGHTING UNIT l Filed April 15, 1959 2 Sheets-sheet 1 l Q f fi// Z/ l ffl-9 2.

WTNESSESZ NVENTORS Frede/'lic C. Wvk/er and Patented Dec. 2, 1941 LIGHTING UNIT Frederic C. Winkler and Steven G. Kovatch,

Lakewood, Ohio, Electric &

assignors to Westinghouse Manufacturing Company, East Pittsburgh, Pa., a corporation of Pennsylvania Application April 13, 1939, Serial No. 267,575

Claims.

Our invention relates, generally, to lighting units, and, more particularly, to lighting units of the industrial type having detachable rellector elements.

Heretofore, various attempts have been made to provide an industrial lighting unit with a quick or readily detachable reilector wherein the lamp socket is of two-part construction, one part being mounted in the reliector extension or neck portion and the other cooperating part in the supporting hood whereby the reflector and lamp may be removed as a unit and the electrical connection to the lamp completed or interrupted by the attachment or detachment of the reector unit from the hood as the case may be.

The use of the prior art devices of this kind has revealed that they have many shortcomings and are, therefore, not entirely satisfactory. In most instances, these devices are too complicated and expensive to make and maintain because of their relatively complicated construction. In other instances, they are difficult to use because of' the manner in which the reector unit is attached to the hood and do not provide a positive and reliable electrical connection to the lamp.

Some of the most desirable features in a unit of this type are the ease with which the reector unit may be attached to and detached from the supporting hood, at the same time ensuring a positive, Ibut easily releasable, locking connection between these two parts when in their normal operating position; provision for eiecting a positive electrical connection when the parts move into locked relation and for ensuring that the live electrical contact members within the hood cannot be short circuited or grounded in any way during the attaching or detaching operation of the two parts.

Since units of this kind are utilized primarily for industrial lighting application in locations where considerable dust, vapor, etc.,are found in large quantities, frequent cleaning or maintenance of the reector and lamps is necessary in order to keep them in eicient operating condition. This necessitates that the reflector unit be removed frequently and since these units are usually suspended from a ceiling or roof, it is quite important and necessary that the reflector unit be easily and readily detached from the hood so that this operation may be accomplished by anyone standing on a ladder or the like and Without the use or" tools of any kind.

Various forms of detachable connectors have been used in the prior art devices, such for example, as a threaded connector, set screws,V

latches of various kinds, etc., all of which require considerable manipulation on the part of the one who is servicing the units and often yare very diicult to manipulate, yespecially from the top of a ladder. In addition, they do not provide for always ensuring a positive electrical connection and do not have a positive locked position which is readily unlocked and which always ensures that the proper electrical connection has been made.

It is, therefore, the object of the present invention, generally stated, to provide a lighting unit of this general character from which all of the foregoing disadvantages have been eliminated; in which the foregoing desirable features have. been embodied; which shall be oi simple and economical construction and which may be readily used with a minimum of maintenance expense.

AV more specic object of our invention is to provide a lighting unit wherein the reilector element and lamp, constituting a unit, may be easilyand quickly detached from and attached to a supporting hood by a limited rotational or turning movement andthe electrical circuit to the lamp completed only when the reflector and hood have become locked together.

Another object of our invention is to provide a lighting unit inV which the rei-lector and lamp holder are detachable from the hood or other supporting member as a unit and in which the electrical circuit to the lamp is not completed until the reflector unit has become securely attached to the hood.

Another object of our invention is to provide, in a lighting unit of this character, for attaching and detaching the reflector unit from the hood by a simple and relatively short rotating or turning movement of the reflector unit with respect to the hood without exerting an upward force on the reector unit, the reector unit and hood being detachablylocked together at the end of the attaching movement.

A further object of our invention is to provide, in a lighting unit wherein the reflector and lamp holder are detachable as a unit from the hood, for detachably connecting these two parts together by utilizing grooves or slots on the interior of the hood which cooperate with lugs carried on the reector extension cap when the end of the reflector is inserted into the hood and rotated or turned through a partial revolution, the grooves terminating in locking recesses which receive the lugs at the end of the turning movement of the reector.

A still funther object is to provide a lighting unit of this character so constructed that it is Fig. 4 is a view of the top of the reflector heel or extension cap showing the shape and Aposition of the locking lugs,

Fig. is a sectional view of the hood portion of the unit showing the resilient mounting of the receptacle,

Fig. 6 is a bottom view of the receptacle of Fig. 5 showing the details of the contact arrangement thereon,

Fig. 7 is la sectional view of the receptacle of Fig. 6 taken along -lines VI-VL Fig. 8 is a top view of the lamp holder` of Fig. 1 and Fig. 9 is a sectional view of the lamp holder of Fig. 1 and also shows a modified form of the reiiector heel portion having a separate extension .cap thereon.

Referring now to the drawings, a lighting unit exemplifying the preferred form of the invention may comprise generally a hood element III, provided with a threaded opening II at the top to receive a pipe, conduit or other support I2 and a reflector I3, having a heel or neck portion I4 which is disposed to intert in telescoping relation with the hood, as shown.

I-n this embodiment Vof the invention provision is made for detachably locking the hood and reflector together in a simple and readily executable manner. The skirt portion I5 of the hood is provided with a plurality of internal slots I6 which are positioned and shaped as shown in the developed views of the skirt 4portion in Figs. 2 and 3. The slots I6 are generally L-shaped and have an entrance portion I1 at the lower edge of the skirt. The transverse portions of the slots are disposed at a slight upward angle and the ends thereof are cut deeper along one side to form a locking recess I8, the purpose of which will be described more in detail hereinafter.

The end of the heel portion I4 of the reflector, which telescopes with the skirt I5, is provided with a plurality of lugs i9 equal to the number of slots IB in the hood and spaced in the same manner. These lugs are received by the slots when the neck `or extension of -the reflector is inserted -within the hood and on relative rotation of the hood and reflector follow the transverse portion of the slots and finally engage the locking recesses I8 which detachably locks the reflector and hood together. Fig. 4 shows the shape and position of one of the lugs I8 on the heel portion I4 of the reiiector. In Fig. 2 the dotted outline of one of the lugs I9 shows the position of the lug in the 'locked position.

In order to provide for supporting and conducting current to a lamp (not shown) and for permitting the removal of the reflector and lamp as a unit from the hood, a two-piece socket is utilized. One part of the socket, which may be termed the receptacle or wiring base 2 I, is mounted within the hood II0 and the other cooperating part, which may be termed the lamp holder 22, is

mounted within the heel portion I4, of the reflector as shown in Fig. 1.

AS Shown in Figs. 1, 5. 6 and r1, the receptacle or wiring base 2l, which is preferably of cylindrical shape, is loosely mounted on a pair of stud bolts 23 extending through openings 24 therein and screwed into the upper end of the hood I0. Coil springs 25 are placed on the stud bolts between the wiring base and the inside of the hood which function to urge the wiring base downwardly toward the end of the heel portion I4. The wiring base may be formed of any suitable material such, for example, as porcelain.

As shown in Figs. 6 and '7, the receptacle 2| is provided with a pair of contact elements 26 and 21 mounted in a bottom recess 28 by means of screws 29 which extend through the receptacle from a top recess 36. A terminal screw 3| is p rovided in each contact element for attaching the supply conductors (not shown) thereto in a well known manner.

Each of the contact elements 26 and 21 is provided with nger portions 32 extending inwardly as shown in Fig. 6 which are exposed on the bottom of the base, and which constitute the live terminals of the unit.

The cooperating lamp holder 22 is shown in Figs. 8 and 9 and comprises a base portion 33, of insulating material, and an integral depending cylindrical skirt portion 34 which houses the threaded shell 35.

As shown in Fig. 1, aswell as in Fig. 8, the lamp holder 22 is disposed within the heel or neck portion III vof the reflector I3 and is detachably secured thereto by means of screws 36, the upper portion of the lamp holder extending upwardly through a central opening in the top of the heel in an exposed position.

The lamp holder 22 is also provided with contact elements 31 and 38 which are disposed to cooperate with the contact elements 26 and 21 on the receptacle in the hood in establishing an electrical connection to the lamp.

The design and relative positions of the contact elements in the receptacle and lamp holder are such that the electrical connection to the llamp carried by the lamp holder 22 is controlled by the relative movement of the hood and reiectcr unit into and out of locking relation or position. The important function which is accomplished being that the lamp circuit is not completed until the locking position is reached following a predetermined degree of initial relative movement of the hood and reiiector unit, it being understood that the hood is usually the stationary element and the reflector unit the rotatable element. Likewise, with this arrangement the lamp `circuit is automatically interrupted in response to the movement of these parts out of the locking position.

This important function is accomplished in this instance by forming the contact element 31, which cooperated with the ngers 32 of the contact element 21 on the receptacle, in the form of a ring which may be conveniently attached to the lamp holder 22 by the same screws 39 which are used to attach the threaded shell 35.

The contact element 38 which cooperates with the nger 32 of contact element 26 on the receptacle, is formed in the shape of a three-pronged member as shown in Fig. 8 and may be attached to the top of the base portion 33 of the lamp holder by a single screw 4I extending through the base portion as shown in Fig. 9. Contact element 3B is so shaped and positioned that the prongs thereof do not engage the prongs 32 of the contact element 26 on the receptacle when the reiiector heel is inserted into the hood but only engage the prongs 32 on predetermined rotation of the reflector heel with respect tothe hood.

Since the reiiector heel is provided with three locking lugs I9, it is possible to insert it within the hood in any one of three different positions. The contact element 38 is likewise provided with three prongs in order that the lamp circuit will be closed onv rotation of the reflector unit regardless of the position in which the reflector heel is inserted in the hood.

As will be readily understood, when the reflector heel is inserted within the hood, with the lugs I9 in the entrance portions i1 of the slots, the ring contact member 31 on the lamp holder 22 engages the prongs 32 of the contact member 21 on the receptacle ZI. l/Vhen the reector heel is in this position, the lugs I 9 are opposite the transverse portions 2l) of the slots I 6 and, upon rotation of the reector unit without any upward force, are caused to follow the slots to the ends thereof. Since the receptacle 2| is mounted for longitudinal movement relative to the hood against the force of springs 25, it is urged upwardly as the locking lugs I9 follow the upwardly inclined slots i5. At the end of the turning movement of the reflector unit the lugs snap into the locking recesses I8 of the slots and the hood and reflector unit are locked together, the springs 25 functioning to firmly hold these parts in locked relation and also to firmly hold the electrical contact elements of the receptacle and lamp holder in engagement.

It will also be apparent that during the turning or rotating movement of the reflector unit a wiping action of the contact members is obtained thereby insuring good electrical contact. The ring-shaped contactl member 31 on the lamp holder 22 wipes over the prongs 32 of the contact member 21 during the entire movement of the reflector assembly while the multi-pronged contact member 38 wipes over the prongs 32 of contact member 26 during the movement of the reflector assembly into and out ofthe locking position.

'Ihe lugs I9 may be formed by extruding a portion of the reflector heel or extension I4 as shown in Fig. 1 or by providing a separate cap member 45, as shown in Fig. 9, and extruding it to form the lugs. The cap member may be secured to the heel in any suitable manner. In this instance the end of the heel has a slightly reduced diameter and the cap 45 is pressed thereon and held thereon by a plurality of screws 46 which extend through suitable openings in the flange 151 of the cap and engage the nuts i8 attached to the lamp holder. This construction permits the use of a diierent metal for the cap which is more suitable from the standpoint of resisting corrosion and forming into the desired shape. This construction is desirable in the case of enameled reflectors as the cap may be applied after the enameling of the reiiector to provide a surface which cannot be damaged by its engagement with the inside of the hood.

As will be readily understood, any suitable type of lamp holder may be used, such, for example, as those of the shock-absorbing type or pull chain type, all of which would be provided with contact elements similar to the contact elements 31 and 38 of the lamp holder 22.

In view of the foregoing detailed description of a preferred embodiment of our invention, it

will now be apparent that wevhave provided a lighting unit having two important features. The manner in which the reflector unit is attached to the hood and detached therefrom by means of a simple rotational movement of the reflector unit, without requiring an upward force to be exerted on the reflector unit in either of these operations, makes these operations easily and readily performed under the most adverse conditions. In addition, the hood and reiiector unit are securely locked together in such manner that thek reflector unit may be readily detached from the hood.

The other important feature of our invention is the manner in which the electrical circuit to the lamp carried by the reflector is closed and opened in response to the rotational movement of the reflector into and out of locking position. By means of this arrangement the lamp is lighted as the reflector snaps into its locked position, thereby giving an indication that the important operation of locking the two elements together has been effected and that positive electrical connections have been made.

Another important feature of our invention is the provision for ensuring that the live terminals in the hood cannot be short circuited in an accidental manner while the reflector unit is being attached to or detached from the hood which is an important safety feature. This results from the arrangement for locking the hood and rei flector unit together and from the manner in which the electrical connections'are made. The reflector neck or extension cannot Ibe inserted into the hood except at the proper positions determined by the slots and lugs. In addition, the receptacle is mounted a sufficient distance within the hood to make it impossible to engage the live contact members thereof by the outer edge of the reector extension or neck when attempting to insert it into the hood by tilting the reflector, or otherwise. l

Accordingly, it will be understood that our invention provides a lighting unit of safe, simple and rugged construction wherein provision is made for readily attaching and detaching the reflector and lamp as a unit from the supporting hood by a simple rotating or turning movement, and at the same time, making and breaking the electrical circuit to the lamp as the reflector unit is actuated to and from its locked position in the hood.

It may be stated, in conclusion, that, while the illustrated example constitutes a practical embodiment of our invention, we do not wish to limit ourselves strictly to the exact details herein illustrated, since modifications of the same may be made without departing from the spirit of the invention, as defined in the appended claims.

We claim as our` invention:

1. A disconnecting holder for lighting units and the like comprising, an inverted cup-shaped supporting member having a plurality of internal inclined grooves formed on the inner surface thereof circumferentially disposed in generally end to end relation and having longitudinally extending entrance portions at one end and locking recesses at the other end thereof, a wiring base having contact members on the face thereof resiliently mounted within the supporting member on a plurality of stud members for movement toward and away from the open end of the supporting member, said wiring base being loosely mounted on the stud members whereby it may also rock thereabout in a plurality of directions,

a tubular connector member disposed to interi-lt with said supporting member in telescoping relation and having a plurality of circumferentlally disposed external lugs thereon, said lugs being spaced apart to be received by the entrance portions of the grooves and to follow the inclined portions thereof and become seated in the locking recesses thereof on predetermined relative rotational movement between the supporting and connector members, and a lamp socket carried by the connector member in Xed relation thereto and having contact members on an exposed face disposed to cooperate with the contact members on the wiring base to effect circuit closing and opening operations in accordance with the locking and unlocking movements of the supporting and connector members, said wiring base having a lower position within the supporting member such that no downward pressure is exerted against the connector` member through the contact members throughout the travel of the lugs in the entrance portions of the grooves and such that a slight downward pressure is exerted as the lugs travel through the inclined portions of the grooves toward and into the locking recesses.

2. A disconnecting holder for lighting units comprising, a cup-shaped hood member having a plurality of circumferentially disposed internal grooves formed on the interior thereof in generally end-to-end relation, each of said grooves having longitudinal extending entrance portions connecting one end thereof with the rim of the open end of the hood member and locking recesses at the other end thereof, a tubular connector member disposed to intert with the hood member in telescoping relation, said connector member having a plurality of spaced outwardly extending lug portions disposed to be received by the entrance portions of the grooves in the hood member and follow said grooves to the locki,

ing recesses thereof on predetermined rotational movement between the hood and connector members, a wiring base of insulating material mounted within the hood, means for loosely retaining said wiring base in the hood for movement toward and away from the open end thereof, resilient means interposed between the hood member and wiring base for resiliently urging said wiring base toward the open end of the hood member, said wiring base having mounted on the exposed face thereof a pair of contact members having relatively stiff inger portions extending inwardly in generally parallel relation to the face of the wiring base, a lampholder attached to the end of the connector portion which extends within the hood member and having an exposed face portion with a pair of stationary contact members mounted thereon, one of said contact members being of ring-shaped construction and the other of multi-pronged construction, both of said contact members being mounted ilatwise against the exposed face of the lampholder, said ring-shaped contact member being disposed to engage the iinger portions of one of the contact members on the wiring base in abutting relation during the relative movement of the hood and connector members into and out of locking relation and the multi-pronged contact member being disposed to engage the finger portions of the other contact member on the wiring base in the locking position onlyI whereby the lamp circuit is completed only when the hood and connector members become locked together in normal operating relation.

3. A disconnecting holder for lighting units comprising, a tubular connector member provided with spaced circumferentially disposed lugs on the exterior thereof, a lampholder mounted within the connector member with its upper end exposed and having mounted thereon a pair of fixed contact members, an inverted cup-shaped hood disposed to receive the end of the connector member in which the lampholder is mounted in telescoping relation, said hood being provided with a plurality of circumferentially extending slots on the interior thereof disposed in generally end-to-end relation and having upper and lower ledge portions, 'said grooves having at one end thereof longitudinal extending entrance portions terminating at the rim of the hood and terminating at the other end in a locking recess portion the lower ledge portion of which extends below the lower ledge portion of the slot and which are disposed to receive the lugs on the connector member and lock therewith on relative rotation of the hood and connector member when said hood and connector member are placed in telescoping relation, and a wiring base of insulating material mounted within the hood and provided with a pair of inwardly extending iixed con-tact members disposed to be engaged in abutting relation by the contact members on the lampholder, the relative positions of said contact members on the lampholder and wiring base being such that the lamp circuit is completed only when the hood and connector member are in locked relation, said wiring base being movably mounted within the hood for movement toward and away from the open end of the hood and having resilient means urging it in an outward direction, whereby said wiring base exerts through the abutting contact members a force on the connector member to force the lugs thereon into the locking recesses of the grooves in the hood to releasably retain the hood and connector member in locked relation.

4. A disconnecting holder for lighting units comprising, a tubular connector member open at the bottom and closed at the top except for a central opening therein, said connector member having a plurality of locking lugs on the exterior thereof spaced apart circumferentially below the upper end thereof, a lampholder xedly mounted within the upper end of the connector member and having a top face exposed by the central opening in the top of the connector member, a cup-shaped hood disposed to receive the end of the connector member in which the lampholder is positioned in telescoping relation and having a plurality of internal circumferentially disposed grooves positioned in end-toend relation in the same general horizontal plane, said grooves being defined by upper and lower ledges and terminating in locking recesses the lower ledges of which are lower than the lower ledges of the grooves where they join the recesses and also having at their ends opposite from the locking recesses longitudinal entrance portions terminating at the lower edge of the hood to receive the locking lugs on the connector member when said member is inserted into the hood and guide said locking members into the grooves and locking recesses thereof on predetermined relative rotation of the hood and connector member, a wiring oase of insulating material mounted within the hood on guide means which loosely supports said wiring base for movement along the longitudinal axis of the hood and to also permit the wiring base to tilt in a plurality of directions, resilient means within the hood urging the wiring base toward the open end of the hood, said Wiring base and lampholder each having a pair of cooperating contact members xedly mounted on the adjacent faces thereof disposed to become slidably engaged in abutting relation to complete the lamp circuit on the predetermined relative rotational movement of the hood and connector member to bring them into the locking position, one contact element of each pair becoming engaged and disengaged on movement of the connector member into and out of the locking position, said resiliently mounted wiring base functioning to exert a downward pressure against the connector member through the abutting contact members to retain the hood and connector member in locked relation and also functioning to adjust its position within the hood to ensure intimate engagement between the said pairs of contact members.

5. A disconnecting holder for lighting units comprising, a tubular connector, a' separate capmernber mounted upon the end of the connector, said cap-member having a plurality of outwardly extending lug portions spaced apart circumferentially thereof below its upper end, a lampholder mounted within the upper end of the connector having its upper face portion exposed through the end of the connector, an inverted cup-shaped hood for supporting the connector, said hood being adapted to receive the upper end of the connector in telescoping relation and having a plurality of circumferentially disposed upwardly inclined grooves on the interior thereof defined by upper and lower parallel ledge portions, 'said grooves having longitudinal entrance portions connecting one end of each with the rim of the hood `and each terminating at its opposite end in a locking recess disposed to receive the lug portions on the cap-member of the connector and lock the connector and hood together on predetermined relative rotational movement thereof to a locking position, a wiring base of insulating material mounted within the hood on a pair of downwardly extending headed stud members and urged downwardly toward the open end of the hood by spring means interposed between the wiring base and the top of the hood, said studs extending through openings in the wiring base of such diameter as to permit the wiring base to tilt thereon, cooperating pairs of contact elements xedly mounted upon the eX- pcsed adjacent faces of the lampholder and wiring base for closing and opening the lamp circuit, said contact elements being disposed in parallel relation to the faces of the lampholder and wiring base so as to become engaged in sliding abutting relation and at least one pair of said cooperating contact elements being so angularly disposed with respect to the locking recesses of the grooves and the lug portions on the connector as to become engaged to complete the lamp circuit only when the connector and hood are in the locking position, said wiring base functioning to exert a downward pressure through the abutting contact elements at least in the locking position to resiliently retain said hood and connector in locked relation and to align itself with the face of :the lampholder, whereby said cooperating contact elements are engaged in intimate contact relation.

FREDERIC C. WINKLER. STEVEN G. KOVATCI-I. 

